Prior Cataract Surgery Research Articles

Visual perception during phacoemulsification cataract surgery under topical and regional anaesthesia.

To compare the subjective visual experiences of patients during phacoemulsification and intraocular lens (IOL) implantation using regional and topical anaesthesia. A prospective, cohort, questionnaire-based study. The study cohort consisted of 247 patients without pre-existing ocular pathology who underwent routine phacoemulsification and IOL implantation. The mean age of the subjects was 75.4 +/- 9.4 years and 34.5% of them had a history of cataract surgery. Three different methods of local anaesthesia were used: 66 (26.7%) of the patients were given topical anaesthesia (TA); 74 (30.0%) were given sub-Tenon's anaesthesia (SA), and 107(43.3%) were given peribulbar anaesthesia (PA). The patients were interviewed immediately after surgery by theatre staff using a standardized questionnaire that investigated their intraoperative visual experiences. There was no significant difference between the three methods of anaesthesia regarding light perception during the surgery. However, patients undergoing surgery under TA experienced brighter light intensity levels (78.3%) than those given SA (50.0%) and PA (55.7%) (p = 0.02). A total of 69.6% of subjects who received TA reported visual perception of colours during surgery, as opposed to 56.8% of SA recipients and 49.0% of PA recipients (p = 0.02). In addition, patients under TA were more aware of surgical instruments (26.1%) than those under SA (10.8%) and PA (15.9%) (p = 0.08). The vast majority of patients in all three groups found the visual experience to be non-frightening. There were no associations between intraoperative visual impression and age or sex. Although not statistically significant (p = 0.06), prior cataract surgery appeared to alleviate some of the anxiety associated with the visual experience. Patients undergoing regional and topical anaesthesia experience a wide variety of visual sensations during surgery. The differences in visual impressions between the groups may reflect the varying degrees of optic nerve blockade that result from the different anaesthetics.

Pathology of canine cataract surgery complications

AIM: To compare pathological complications arising from 2 methods of canine cataract surgery, manual extracapsular cataract extraction (MECCE) and the more automated phacoemulsification and aspiration (PA). METHODS: Case material presented to the Comparative Ophthalmic Pathology Laboratory, University of North Carolina over the previous 20 years (1979–1999) was searched for cases with a history of prior cataract surgery. Data were obtained from the pathology accession forms, and submitting veterinarians were contacted to verify and complete missing data where possible. The slides were re-examined, histological features of surgical complications were noted and secondary changes recorded. RESULTS: Fourteen canine post-cataract-surgery cases were reviewed, the average age of the group being 7.7 years. Of the 14 eyes, 7 had surgery performed using MECCE, and 7 using PA. Of the 7 eyes that underwent MECCE surgery, 5 were enucleated and diagnosed on both clinical and pathological grounds with glaucoma. Of the 7 eyes that underwent PA, 4 were diagnosed with infectious endophthalmitis. CONCULSIONS: Complications observed were related to the surgical technique performed. Failures of manual extracapsular surgical procedures were more commonly associated with postoperative synechia and glaucoma, compared with failures of phacoemulsification, which were more commonly associated with infection and rhegmatogenous retinal detachments. CLINICAL RELEVANCE: To minimise post surgical complications, MECCE should be accompanied by rigorous efforts to reduce surgically induced inflammation, while PA should be performed using excellent aseptic technique. It is important with both techniques to totally remove cortical material while maintaining the integrity of the posterior capsule.

Relationships between laser flare photometry values and complications of uveitis.

To determine whether relationships exist between elevated laser flare photometry values and common abnormalities and complications associated with uveitis. We retrospectively studied all patients with uveitis on whom laser flare photometry measurements ("flare") were obtained (N = 111) at 2 academic medical centers. The first laser flare photometry values obtained for each patient were compared with the presence or absence of the following abnormalities or complications associated with uveitis: keratic precipitates, posterior synechiae, cataract, macular edema, optic disc edema, and glaucoma. In bilateral cases, the eye with the higher flare was used in primary analyses. Flare was significantly higher in patients with posterior synechiae (P<.001) and in those with macular edema (P =.02) than in patients with uveitis who did not have these complications. Flare was significantly higher in patients with prior cataract surgery or cataract at the study visit than in those without cataracts (P =.001). There was no significant difference in flare between patients with and without keratic precipitates, optic disc edema, or glaucoma. No relationships were found between abnormalities or complications and the level of inflammatory cells or flare as determined by clinical assessment. We also identified an inverse relationship between flare and visual acuity that was not completely explained by the presence of complications in a stepwise regression model. Although causal relationships were not established, associations between flare and some complications of uveitis suggest that aqueous humor protein may be an important factor in the development of these problems. Consequently, laser flare photometry could play a role in predicting outcomes or monitoring therapy for patients with uveitis.

Operated and unoperated cataract in Australia

To quantify the prevalence of cataract, the outcomes of cataract surgery and the factors related to unoperated cataract in Australia. Participants were recruited from the Visual Impairment Project: a cluster, stratified sample of more than 5,000 Victorians aged 40 years and over. At examination sites interviews, clinical examinations and lens photography were performed. Cataract was defined in participants who had: had previous cataract surgery, cortical cataract greater than 4/16, nuclear greater than Wilmer standard 2, or posterior subcapsular greater than 1 mm2. The participant group comprised 3,271 Melbourne residents, 403 Melbourne nursing home residents and 1,473 rural residents. The weighted rate of any cataract in Victoria was 21.5%. The overall weighted rate of prior cataract surgery was 3.79%. Two hundred and forty-nine eyes had had prior cataract surgery. Of these 249 procedures, 49 (20%) were aphakic, 6 (2.4%) had anterior chamber intraocular lenses and 194 (78%) had posterior chamber intraocular lenses. Two hundred and eleven of these operated eyes (85%) had best-corrected visual acuity of 6/12 or better, the legal requirement for a driver's license. Twenty-seven (11%) had visual acuity of less than 6/18 (moderate vision impairment). Complications of cataract surgery caused reduced vision in four of the 27 eyes (15%), or 1.9% of operated eyes. Three of these four eyes had undergone intracapsular cataract extraction and the fourth eye had an opaque posterior capsule. No one had bilateral vision impairment as a result of cataract surgery. Surprisingly, no particular demographic factors (such as age, gender, rural residence, occupation, employment status, health insurance status, ethnicity) were related to the presence of unoperated cataract. Although the overall prevalence of cataract is quite high, no particular subgroup is systematically underserviced in terms of cataract surgery. Overall, the results of cataract surgery are very good, with the majority of eyes achieving driving vision following cataract extraction.

Lens opacities, demographic factors and nutritional supplements in the Barbados Eye Study.

This study evaluated the association of age-related lens opacities with the use of nutritional supplements and demographic factors among 4314 black participants (> or = 40 years) in the population-based Barbados Eye Study. Lenses were classified at the slit lamp by the Lens Opacities Classification System II (LOCS II); a score > or = 2 was used to define the presence of gradable lens opacities, by type. Lens changes also included prior cataract surgery or cataract too advanced to grade. Associations with risk factors were evaluated by logistic regression analyses. The study identified 1800 individuals with lens changes in at least one eye; 229 had nuclear opacities only; 851 had cortical opacities only. Older age and indicators of lower socioeconomic status (low education and/or non-professional occupation), were positively associated with both nuclear (odds ratio [OR] = 1.90) and cortical (OR = 1.47) opacities. Women had an increased risk of cortical opacities (OR = 1.41). Regular users of nutritional supplements were less likely to have lens changes (OR = 0.78) and, specifically, cortical opacities (OR = 0.77). The association with nutritional supplements was present in those < 70 years, but not at older ages. The study supports the association of lower socioeconomic status with lens changes, including nuclear and cortical lens opacities. The findings also suggest that regular users of nutritional supplements have a one-fourth lower risk of lens changes and particularly, of cortical opacities; a result seen at ages under 70 years. The associations with potentially modifiable factors indicate the need for further evaluations, given the high prevalence of lens opacities.

Tenon's Cyst Formation After Trabeculectomy With Mitomycin C

One hundred eyes of 100 patients in whom Tenon's cysts (TCs) developed in the early postoperative period following trabeculectomy with mitomycin C were retrospectively studied to determine their incidence, possible risk factors associated with their development, and the clinical course of the patients in whom they occurred. The incidence of TC formation was 29/100 (29%). Significantly more cysts developed in the men than in the women. There were no significant differences between those patients in whom TCs developed and those in whom they did not in terms of age, race, type of preoperative medications, mean preoperative intraocular pressure (IOP), prior argon laser trabeculoplasty, prior trabeculectomy, prior Tenon's cyst formation, or prior cataract surgery. The 29 patients in whom a Tenon's cyst developed had a mean follow up of 22.0 +/- 12.9 weeks, with a mean IOP at the last examination of 14.2 +/- 6.3 mm Hg (as compared with 20.7 +/- 8.3 mm Hg at the time of diagnosis). One patient required a repeat trabeculectomy with mitomycin C. Two patients required bleb needling, subsequent TC excision, and eventual seton placement. Of the remaining 26, 14 (54%) required no glaucoma medication for IOP control, 11 (42%) required one, and 1 (4%) required two.

Preoperative Iris Rubeosis and Diabetic Vitrectomy Results

Six hundred and forty-five patients undergoing pars plana vitrectomy for diabetic retinopathy without preoperative iris rubeosis were followed for six months and compared with 69 patients that had preoperative pupillary rubeosis and 30 patients that had preoperative peripheral iris and/or angle rubeosis. Preoperatively, the patients' general characteristics were quite similar, but those cases with peripheral iris rubeosis had poorer visual acuities due to a higher incidence of dense vitreous hemorrhages (70%), as compared with those without rubeosis (56%), and a higher incidence of cataracts and prior cataract surgery. The operative procedures were complicated by retinal holes in 40% of the cases with peripheral rubeosis compared with 24% of those without rubeosis. Postoperatively, elevated intraocular pressures occurred in 67% of the cases with preoperative peripheral rubeosis compared with 58% of those with preoperative pupillary rubeosis and 37% of those without preoperative rubeosis. Postoperative steroids were required more frequently in those eyes with preoperative rubeosis. Six months after vitrectomy, the visual results were much better in those eyes without preoperative rubeosis, but 27% of the cases with preoperative peripheral rubeosis had obtained 6/60 visual acuity or better. As expected, there was a direct correlation between the extent of iris rubeosis at the preoperative examination and at the six-month postoperative examination. Regression of preoperative rubeosis definitely occurred in some eyes during the postoperative period. Phthisis had occurred or was occurring in 23% of the eyes with preoperative peripheral rubeosis compared with 15% of the eyes without preoperative rubeosis or with rubeosis confined to the pupil. Determination of the exact incidence of neovascular glaucoma during the six-month follow-up period was difficult, but was probably 33% for those cases with preoperative peripheral rubeosis, as compared with 17% for those without preoperative rubeosis.Opacities of the anterior segments prevented evaluation of more posterior structures in many cases, especially those with preoperative peripheral rubeosis of which 47% had obscured vitreous cavities, as compared with 20% of those without preoperative rubeosis. Of those that could be visualized, the vitreous cavities were usually clear and the retinas attached.